Rotary regenerator having concentric cylindrical matrices



June 25, 1968 s. STRANITI ETAL ROTARY REGENERATOR HAVING CONCENTRIC CYLINDRICAL MATRICES 3 Sheets-Sheet l Filed June 2l, 1967 June 25, 1968 s. STRANITI ETAL 3,389,746

ROTARY REGENERATOR HAVING CONCENTRIC CYLINDRICAL MATRICES Filed June 2l, 1967 5 Sheets-Shea?I 2 INVENTORS. SALVATORE STRANITI RICHARD E. KISH E g i W71 Lil $7.624. T/EYS.

June 25, 1968 S. STRANITI ETAL ROTARY REGENERATOR HAVING CONCENTRIC CYLINDRICAL MATRICES `Filed June 2l, 1967 GAS OUT 3 Sheets-Sheet 3 INVENTORS. SALVATORE STRANITI RICHARD E.A K ISH BY 7,4 x17,

@ifE QRNEYS United States Patent O 3,389,746 ROTARY REGENERATOR HAVING CONCENTRIC CYLINDRICAL MATRICES Salvatore Straniti, Orange, and Richard E. Kish, Trumbull, Conn., assignors to Avco Corporation, Stratford,

Conn., a corporation of Delaware Filed .lune 21, 1967, Ser. No. 647,664 3 Claims. (Cl. 165-9) ABSTRACT OF THE DISCLOSURE A heat exchanger is constructed with a plurality of concentrically positioned rotating matrices. Each matrix is divided circumferentially into a plurality of segments and the mounting for the matrices provides for the radial ilow of tluids therethrough. The hot and col-d gases passing through the heat exchanger are maintained separated, except for minimum crossover, by means of face contact running seals.

Prior art The prior art teaches two general types of rotary regenerators for use in conjunction with gas turbine engines. The disk type of rotary regenerator provides axial gas flow through the rotating matrix and permits facetype sealing. Face-type sealing is generally regarded as advantageous because the extreme temperature changes which occur with each revolution of the matrix do not signiiicantly atiect the seal. However, the disk type of regenerator has a short axial dimension, `and therefore requires -a large radial dimension for elective heat exchanging. In many gas turbine applications, space limitations will not permit the required diameter.

The second type uses a rotating hollow cylindrical drum-type matrix through which the uid flows radially. This arrangement is advantageous in that an effective heat exchange area can be provided within a given diameter by increasing the axial dimension of the matrix to the extent necessary. However, the cylindrical matrix requires axial seals which are diiicult to maintain, particularly Where large temperature gradients occur, 4and thus is inferior to the disk type matrix in this regard.

Summary The present invention combines the advantages of both the disk and drum type of regenerators by using a plurality of rotating concentric cylindrical matrices. The matrices and the uid-flow passages are divided into many segments by means of radial ribs, and the fluid-in and uid-out passages are separated from one another by walls concentric with the matrices. With this construction all face contact seals of the kind found in -disk-type regenerators are used. These seals are relatively insensitive to thermal gradients, and can be kept in contact either by springs or by pressure balancing. Furthermore, the axial dimension of the matrix can be maintained at a minimum for -any given matrix diameter.

Objects It is an object of this invention to provide a rotary regenerator comprised of a plurality of concentric cylindrical matrices, the sealing between the fluid being accomplished by face contact seals.

Another object of this invention is to provide a vrotary regenerator having an axial dimension comparable to a disk-type rotary regenerator, but having a diameter comparable to a cylindrical-type regenerator and being sealed with face contact seals.

Still another object of this invention is to provide a 3,389,746 Patented June 25, 1968 rotary regenerator having a plurality of concentric heat exchanging matrices, the fluid-How passages through said regenerator ybeing divided into a plurality of segments deiine'd by a plurality of radical ribs and concentric walls,

the rotating seals for the inlets and outlets being face contact seals.

Drawings First embodiment The disclosed rotary regenerator is intended for use in combination with a gas turbine engine, the heat of the exhaust gases being exchanged with 4the heat of the intake air for preheating the air prior to combustion. Referring to the embodiment shown in FIGURES 1 and 2 of the drawings, the regener-ator is contained within a stationary, generally cylindrical housing 10, the forward end of which is closed by a sectored wall 12 and the rear end of which is closed by a sectored wall 14. The wall 12 is provided with a plurality of circular air outlet openings 16 which deliver heated compressed air -to the engine (not shown) and an exhaust gas inlet 18 through which the exhaust gases from the engine enter the regenerator. The wall 14 is similarly provided with a plurality of air inlet openings 20 formed in the shape of lan intake scoop and an exhaust gas outlet opening 22. As best seen in FIGURE 2, the openings 16 an-d 20 in walls 12 and 14, lrespectively, are formed in an approximately -degree sector, while the openings 18 and 22 occupy the remainder ofthe wall space.

The rotary regenerator, generally indicated at 24, is made up of a composite cylindrical structure which iS rotatably mounted within the housing 10 on bearings 26. In the embodiment shown, the regenerator 24 consists of four heat exchanging matrices 28a to 28d, each of which is supported between adjacent concentric drums 30, 32, 34, 36, and 38. The concentric drums 30, 32, 34, 36, and 38 are provided with radially outwardly extending end walls 40a, 4Gb, 40C, and 40d, respectively, while the drums 32, 34, 36, and 38 are provided with radially inwardly extending end walls 42a, 42b, 42e, Iand 42d, respectively. The matrix 28a is iixedly supported between the lips 44a and 46a on the walls 40a and 42a, respectively. Similarly, the matrices 28b, 28e, and 28d are iixedly supported between the lips 44b, 44e, and 44d Iand 46b, 46c, and 46d formed on the walls 40b to 40d and 4211 to 42d, respectively. When assembled, the drums and matrices form a composite structure having iluid passages A1, A2, B1, B2, C1, C2, D1, and D2 formed therein.

As best seen in FIGURE 2, each of the passages is segmented by circumferentially spaced radial ribs 49a and 51a -to 49d and 51d, the ribs 49a to 49d extending radially inwardly from their associated drums 32 to 38, respectively, and the ribs 51a to 51d extending radially outwardly from their associated drums 30 to 36, respectively.

Air entering the air inlet opening 20 is directed-by bales 50 to the regenerator 24 where it enters the segmented passages A2 to D2. The air is then directly radially through each of the matrices 28a to 28d and into the segmented passages A1 to D1 from which the air exits through the openings 16 in the Wall 12. The exhaust gases from the gas turbine engine passing through the opening 18 enter the passages A1 to D1, pass through the matrices 3 28a to 28d and exit from the passages A2 to D2 through the opening 22 in the wall 14.

For the purposes of sealing the inlet exhaust gSeS from the outlet air, the wall 12 is provided with several seals. An inner annular seal S2 is positioned coaxially with the rotating matrix 24 with its sealing surface maintained in face contact with the end wall 54 of the drum 30. The seal 52 is maintained within an appropriately contoured annular groove 55 in the wall 12 and is maintained against the Wall 54 by means of springs 56. Similarly, an outer annular seal S8 is maintained. Seal 58 is positioned within an annular grove 60 in the wall 12 and is maintained under pressure against the end Wall 42d by means of springs 62. As best seen in FIGURE 2, the inner and outer seals are interconnected by means of radial ribs 64 (see FIGURE 2) which are in face contact with all of the end walls 12a-42d.

The inlet air is similarly sealed from the outlet exhaust gases at the rear of the heat exchanger by means of an inner annular seal 66 and `an outer annular seal 68 maintained in compression against the opposite end walls of the drums 30 and 38, respectively. Radial ribs 70 interconnect the seals 66 and 68 in the same manner as the seals 52 and 58 are interconnected.

Second embodiment The second embodiment illustrated in FIGURE 3 is the same as the embodiment of FIGURES 1 and 2 with the exception that FIGURE 3 used concentric drums 30'-38 which are truncated cones rather than cylinders. This conguration serves to provide a more eieient flow of fluid through the apparatus.

We claim:

1. A rotary heat exchanger for transferring the heat from a relatively hot tluid to a relatively cool fluid, the combination comprising:

a stationary, generally cylindrical housing having end walls, the opposing end walls being provided with an opposing inlet and outlet port for said relatively hot fluid and an inlet and outlet port for said relatively cool tiuid;

a heat exchanger rotatably mounted within said housing, said heat exchanger comprising a plurality of hollow drums, each of said drums` having iirst and 4. second annular flanges at opposite ends thereof, the irst flange extending radially inwardly and the second ange extending radially outwardly;

a plurality of cylindrical heat exchanging matrices each concentrically supported between the inwardly extending and outwardly extending flanges of adjacent drums, the surfaces of said drums and said anges forming a plurality of passages for directing said iluids through each of said matrices;

a plurality of radial ribs secured to the surfaces of each of said drums and extending to each matrix face for circumferentially segmenting said passages, said ribs extending axially the entire length of said drums between opposing flanges; and

sealing .means aflixed to each of said end walls and maintained in running contact with said flanges, said sealing means separating the ports on each wall for preventing the mixture of said relatively hot fluids and said relatively cool fiuids.

2. The invention as defined in claim 1 wherein said hollow drums are truncated cones.

3. The invention as deiined in claim 1 wherein each of said sealing means is provided for maintaining the relatively hot uid substantially separated from the relatively cool fluid and comprises first and second station-ary, annular seals in face contact with the flanges of the innermost and outermost drums and first and second radial ribs extending between said first and second annular seals, the segments between said ribs deiining said ports.

References Cited UNITED STATES PATENTS 2,944,798 7/ 1960 Muller 165-10 2,680,008 6/ 1954 Karlsson 165-8 2,892,615 6/1959 Misener 165-7 v3,079,991 3/ 1963 Evans et al. 165-7 FOREIGN PATENTS 739,904 11/ 1955 Great. Britain.

776,532 6/ 1957 Great Brit-ain.

776,533 6/ 1957 Great Britain.

ROBERT A OLEARY, Primary Examiner.

A. W. DAVIS, Assistant Examiner. 

